X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=README;h=6715a1f669d9b1223e8fa69327ab0652bef76bae;hp=25430a70bb7236f85caea254b215128f2f9f29b1;hb=HEAD;hpb=cee5f3ac7874a5f3d1ee4d4c3a56dc49e9f0ef0a diff --git a/README b/README deleted file mode 100644 index 25430a70..00000000 --- a/README +++ /dev/null @@ -1,381 +0,0 @@ - INTRODUCTION - -This is wimlib version 1.7.0 (June 2014). wimlib is a C library for -creating, modifying, extracting, and mounting files in the Windows Imaging -Format (WIM files). These files are normally created using the ImageX -(imagex.exe) or Dism (Dism.exe) utilities on Windows, but wimlib is distributed -with a free implementation of ImageX called "wimlib-imagex" for both UNIX-like -systems and Windows. - - INSTALLATION - -To install wimlib and wimlib-imagex on Windows you simply need to download and -extract the ZIP file containing the latest binaries from the SourceForge page -(http://sourceforge.net/projects/wimlib/), which you may have already done. - -To install wimlib and wimlib-imagex on UNIX-like systems (with Linux being the -primary supported and tested platform), you must compile the source code, which -is also available at http://sourceforge.net/projects/wimlib/. Alternatively, -check if a package has been prepared for your Linux distribution. Example files -for Debian and RPM packaging are in the debian/ and rpm/ directories. - - WIM FILES - -A Windows Imaging (WIM) file is an archive designed primarily for archiving -Windows filesystems. However, it can be used on other platforms as well, with -some limitations. Like some other archive formats such as ZIP, files in WIM -archives may be compressed. WIM files support multiple compression formats, -including LZX, XPRESS, and LZMS. All these formats are supported by wimlib. - -A WIM file consists of one or more "images". Each image is an independent -top-level directory structure and is logically separate from all other images in -the WIM. Each image has a name as well as a 1-based index in the WIM file. To -save space, WIM archives automatically combine all duplicate files across all -images. - -A WIM file may be either stand-alone or split into multiple parts. Split WIMs -are read-only and cannot be modified. - -Since version 1.6.0, wimlib also supports ESD (.esd) files, except when -encrypted. These are still WIM files but they use a newer version of the file -format. - - IMAGEX IMPLEMENTATION - -wimlib itself is a C library, and it provides a documented public API (See: -http://wimlib.sourceforge.net) for other programs to use. However, it is also -distributed with a command-line program called "wimlib-imagex" that uses this -library to implement an imaging tool similar to Microsoft's ImageX. -wimlib-imagex supports almost all the capabilities of Microsoft's ImageX as well -as additional capabilities. wimlib-imagex works on both UNIX-like systems and -Windows, although some features differ between the platforms. - -Run `wimlib-imagex' with no arguments to see an overview of the available -commands and their syntax. For additional documentation: - - * If you have installed wimlib-imagex on a UNIX-like system, you will find - further documentation in the man pages; run `man wimlib-imagex' to get - started. - - * If you have downloaded the Windows binary distribution, you will find the - documentation for wimlib-imagex in PDF format in the "doc" directory, - ready for viewing with any PDF viewer. Please note that although the PDF - files are converted from UNIX-style "man pages", they do document - Windows-specific behavior when appropriate. - - COMPRESSION RATIO - -wimlib (and wimlib-imagex) can create XPRESS, LZX, or LZMS compressed WIM files. -wimlib includes its own compression codecs and does not use the compression API -available on some versions of Windows. - -I have gradually been improving the compression codecs in wimlib, and in some -cases they now outperform and outcompress the equivalent Microsoft -implementations. Although results will vary depending on the data being -compressed, in the table below I present the results for a common use case: -compressing an x86 Windows PE image. Each row displays the compression type, -the size of the resulting WIM file in bytes, and how many seconds it took to -create the file. When applicable, the results with the equivalent Microsoft -implementation in WIMGAPI is included. - - ============================================================================= - | Compression type || wimlib (v1.7.0) | WIMGAPI (Windows 8.1) | - ============================================================================= - | None [1] || 361,182,560 in 7.6s | 361,183,674 in 11.9s | - | XPRESS [2] || 138,992,007 in 11.5s | 140,416,657 in 13.9s | - | LZX (quick) [3] || 131,428,113 in 15.2s | N/A | - | LZX (normal) [4] || 126,807,853 in 58.9s | 127,259,566 in 55.2s | - | LZX (slow) [5] || 126,085,971 in 125s | N/A | - | LZMS (non-solid) [6] || 122,082,982 in 59.8s | N/A | - | LZMS (solid) [7] || 92,171,126 in 260s | 88,742,356 in 556s | - ============================================================================= - -Notes: - [1] '--compress=none' for wimlib-imagex; - '/compress:none' for DISM. - - [2] '--compress=fast' or '--compress=XPRESS' for wimlib-imagex; - '/compress:fast' for DISM. - Compression chunk size is 32768 bytes, the default for XPRESS. - - [3] No compression option specified to wimlib-imagex; - no known equivalent for DISM. - Compression chunk size is 32768 bytes, the default for LZX. - - [4] '--compress=maximum' or '--compress=LZX' for wimlib-imagex; - '/compress:maximum' for DISM. - Compression chunk size is 32768 bytes, the default for LZX. - - [5] '--compress=maximum --compress-slow' for wimlib-imagex; - no known equivalent for DISM. - Compression chunk size is 32768 bytes, the default for LZX. - - [6] '--compress=recovery' or '--compress=LZMS' for wimlib-imagex; - no known equivalent for DISM. - Compression chunk size is 131072 bytes, the default for LZMS. - - [7] '--compress=recovery --solid' or '--compress=LZMS --solid' for - wimlib-imagex. Should be '/compress:recovery' for DISM, but it doesn't - work; I called WIMGAPI directly instead. - Compression chunk size in solid blocks is 67108864 bytes in both cases. - -I did the timings on Windows 8.1 running in a virtual machine so that -side-by-side comparisons with the Microsoft implementation would be possible. -However, do note that wimlib may have even better performance on other operating -systems such as Linux. I used the 64-bit builds of both programs. - -The compression ratio provided by wimlib is also competitive with commonly used -archive formats. Below are file sizes that result when the Canterbury corpus is -compressed with wimlib (v1.7.0), WIMGAPI (Windows 8), and some other -formats/programs: - - ================================================= - | Format | Size (bytes) | - ================================================= - | tar | 2,826,240 | - | WIM (WIMGAPI, None) | 2,814,278 | - | WIM (wimlib, None) | 2,813,856 | - | WIM (WIMGAPI, XPRESS) | 825,410 | - | WIM (wimlib, XPRESS) | 792,024 | - | tar.gz (gzip, default) | 738,796 | - | ZIP (Info-ZIP, default) | 735,334 | - | tar.gz (gzip, -9) | 733,971 | - | ZIP (Info-ZIP, -9) | 732,297 | - | WIM (wimlib, LZX quick) | 722,196 | - | WIM (WIMGAPI, LZX) | 651,766 | - | WIM (wimlib, LZX normal) | 649,204 | - | WIM (wimlib, LZX slow) | 639,618 | - | WIM (wimlib, LZMS non-solid) | 592,136 | - | tar.bz2 (bzip, default) | 565,008 | - | tar.bz2 (bzip, -9) | 565,008 | - | WIM (wimlib, LZMS solid) | 525,270 | - | WIM (wimlib, LZMS solid, slow) | 521,700 | - | WIM (WIMGAPI, LZMS solid) | 521,232 | - | tar.xz (xz, default) | 486,916 | - | tar.xz (xz, -9) | 486,904 | - | 7z (7-zip, default) | 484,700 | - | 7z (7-zip, -9) | 483,239 | - ================================================= - -Note: WIM does even better on directory trees containing duplicate files, which -the Canterbury corpus doesn't have. - - NTFS SUPPORT - -WIM images may contain data, such as alternate data streams and -compression/encryption flags, that are best represented on the NTFS filesystem -used on Windows. Also, WIM images may contain security descriptors which are -specific to Windows and cannot be represented on other operating systems. -wimlib handles this NTFS-specific or Windows-specific data in a -platform-dependent way: - - * In the Windows version of wimlib and wimlib-imagex, NTFS-specific and - Windows-specific data are supported natively. - - * In the UNIX version of wimlib and wimlib-imagex, NTFS-specific and - Windows-specific data are ordinarily ignored; however, there is also special - support for capturing and extracting images directly to/from unmounted NTFS - volumes. This was made possible with the help of libntfs-3g from the - NTFS-3g project. - -For both platforms the code for NTFS capture and extraction is complete enough -that it is possible to apply an image from the "install.wim" contained in recent -Windows installation media (Vista, Windows 7, or Windows 8) directly to an NTFS -filesystem, and then boot Windows from it after preparing the Boot Configuration -Data. In addition, a Windows installation can be captured (or backed up) into a -WIM file, and then re-applied later. - - WINDOWS PE - -A major use for wimlib and wimlib-imagex is to create customized images of -Windows PE, the Windows Preinstallation Environment, on either UNIX-like systems -or Windows without having to rely on Microsoft's software and its restrictions -and limitations. - -Windows PE is a lightweight version of Windows that can run entirely from memory -and can be used to install Windows from local media or a network drive or -perform maintenance. It is the operating system that runs when you boot from -the Windows installation media. - -You can find Windows PE on the installation DVD for Windows Vista, Windows 7, or -Windows 8, in the file `sources/boot.wim'. Windows PE can also be found in the -Windows Automated Installation Kit (WAIK), which is free to download from -Microsoft, inside the `WinPE.cab' file, which you can extract natively on -Windows, or on UNIX-like systems if you install either the `cabextract' or -`p7zip' programs. - -In addition, Windows installations and recovery partitions frequently contain a -WIM containing an image of the Windows Recovery Environment, which is similar to -Windows PE. - -A shell script `mkwinpeimg' is distributed with wimlib on UNIX-like systems to -ease the process of creating and customizing a bootable Windows PE image. - - DEPENDENCIES - -This section documents the dependencies of wimlib and the programs distributed -with it, when building for a UNIX-like system from source. If you have -downloaded the Windows binary distribution of wimlib and wimlib-imagex then all -dependencies were already included and this section is irrelevant. - -* libxml2 (required) - This is a commonly used free library to read and write XML files. You - likely already have it installed as a dependency for some other program. - For more information see http://xmlsoft.org/. - -* libfuse (optional but highly recommended) - Unless configured with --without-fuse, wimlib requires a non-ancient - version of libfuse to be installed. Most Linux distributions already - include this, but make sure you have the libfuse package installed, and - also libfuse-dev if your distribution distributes header files - separately. FUSE also requires a kernel module. If the kernel module - is available it will automatically be loaded if you try to mount a WIM - file. For more information see http://fuse.sourceforge.net/. FUSE is - also available for FreeBSD. - -* libntfs-3g (optional but highly recommended) - Unless configured with --without-ntfs-3g, wimlib requires the library - and headers for libntfs-3g version 2011-4-12 or later to be installed. - Versions dated 2010-3-6 and earlier do not work because they are missing - the header xattrs.h (and the file xattrs.c, which contains functions we - need). libntfs-3g version 2013-1-13 is compatible only with wimlib - 1.2.4 and later. - -* OpenSSL / libcrypto (optional) - wimlib can use the SHA1 message digest code from OpenSSL instead of - compiling in yet another SHA1 implementation. (See LICENSE section.) - -* cdrkit (optional) -* mtools (optional) -* syslinux (optional) -* cabextract (optional) - The `mkwinpeimg' shell script will look for several other programs - depending on what options are given to it. Depending on your Linux - distribution, you may already have these programs installed, or they may - be in the software repository. Making an ISO filesystem requires - `mkisofs' from `cdrkit' (http://www.cdrkit.org). Making a disk image - requires `mtools' (http://www.gnu.org/software/mtools) and `syslinux' - (http://www.syslinux.org). Retrieving files from the Windows Automated - Installation Kit requires `cabextract' (http://www.cabextract.org.uk). - - CONFIGURATION - -This section documents the most important options that may be passed to the -"configure" script when building from source: - ---without-ntfs-3g - If libntfs-3g is not available or is not version 2011-4-12 or later, - wimlib can be built without it, in which case it will not be possible to - apply or capture images directly to/from NTFS volumes. - ---without-fuse - If libfuse or the FUSE kernel module is not available, wimlib can be - compiled with --without-fuse. This will remove the ability to mount and - unmount WIM files. - ---without-libcrypto - Build in functions for SHA1 rather than using external SHA1 functions - from libcrypto (part of OpenSSL). The default is to use libcrypto if it - is found on the system. - ---disable-multithreaded-compression - By default, data will be compressed using multiple threads when writing - a WIM, unless only 1 processor is detected. Specify this option to - disable support for this. - ---enable-ssse3-sha1 - Use a very fast assembly language implementation of SHA1 from Intel. - Only use this if the build target supports the SSSE3 instructions. - ---disable-error-messages - Save some space by removing all error messages from the library. - ---disable-assertions - Remove assertions included by default. - - PORTABILITY - -wimlib has primarily been tested on Linux and Windows (primarily Windows 7, but -also Windows XP and Windows 8). - -wimlib may work on FreeBSD and Mac OS X. However, this is not well tested. If -you do not have libntfs-3g 2011-4-12 or later available, you must configure -wimlib with --without-ntfs-3g. On FreeBSD, before mounting a WIM you need to -load the POSIX message queue module (run `kldload mqueuefs'). - -The code has primarily been tested on x86 and x86_64 CPUs, but it's written to -be portable to other architectures and I've also tested it on ARM. However, -although the code is written to correctly deal with endianness, it has not yet -actually been tested on a big-endian architecture. - - REFERENCES - -The WIM file format is partially specified in a document that can be found in -the Microsoft Download Center. However, this document really only provides an -overview of the format and is not a formal specification. - -With regards to the supported compression formats: - -- Microsoft has official documentation for XPRESS that is of reasonable quality. -- Microsoft has official documentation for LZX but it contains errors. -- There does not seem to be any official documentation for LZMS, so my comments - and code in src/lzms-decompress.c may in fact be the best documentation - available for this particular compression format. - -The code in ntfs-3g_apply.c and ntfs-3g_capture.c uses the NTFS-3g library, -which is a library for reading and writing to NTFS filesystems (the filesystem -used by recent versions of Windows). See -http://www.tuxera.com/community/ntfs-3g-download/ for more information. - -The LZX decompressor (lzx-decompress.c) was originally based on code from the -cabextract project (http://www.cabextract.org.uk). The LZX compressor -(lzx-compress.c) was originally based on code written by Matthew Russotto -(www.russotto.net/chm/). However I have since rewritten and made many -improvements to both the decompressor and compressor. - -lz_hash.c contains LZ77 match-finding code that uses hash chains. It is based -on code from zlib but I have since rewritten it. - -lz_bt.c contains LZ77 match-finding code that uses binary trees. It is based on -code from liblzma but I have since rewritten it. - -A limited number of other free programs can handle some parts of the WIM -file format: - - * 7-zip is able to extract and create WIMs (as well as files in many - other archive formats). However, wimlib is designed specifically to handle - WIM files and provides features previously only available in Microsoft's - implementation, such as the ability to mount WIMs read-write as well as - read-only, the ability to create compressed WIMs, and the correct handling - of security descriptors and hard links. - * ImagePyX (https://github.com/maxpat78/ImagePyX) is a Python program that - provides similar capabilities to wimlib-imagex. One thing to note, though, - is that it does not support compression and decompression by itself, but - instead relies on external native code, such as the codecs from wimlib. - -If you are looking for an archive format that provides features similar to WIM -but was designed primarily for UNIX, you may want to consider SquashFS -(http://squashfs.sourceforge.net/). However, you may find that wimlib works -surprisingly well on UNIX. It will store hard links and symbolic links, and it -has optional support for storing UNIX owners, groups, modes, and special files -such as device nodes and FIFOs. Actually, I use it to back up my own files on -Linux! - - LICENSE AND DISCLAIMER - -See COPYING for information about the license. - -wimlib is independently developed and does not contain any code, data, or files -copyrighted by Microsoft. It is not known to be affected by any patents. - -On UNIX-like systems, if you do not want wimlib to be dynamically linked with -libcrypto (OpenSSL), configure with --without-libcrypto. This replaces the SHA1 -implementation with built-in code and there will be no difference in -functionality. - -wimlib comes with no warranty whatsoever. Please submit a bug report (to -ebiggers3@gmail.com) if you find a bug in wimlib and/or wimlib-imagex. - -Be aware that some parts of the WIM file format are poorly documented or even -completely undocumented, so I've just had to do the best I can to read and write -WIMs that appear to be compatible with Microsoft's software.